Yes, the irritating part about bayer is varying luminance resolution, because it suddenly drops the plots as far as detail before natural factors like DOF would cause decay.

The other annoying part is the color artifacts, which bring utterly unexpected colors into view where none should be simply based on a pattern.

The Quattro should be immune to simply "made up" colors, the worst I can possibly see happening is some kind of color bleeding. But because of the top layers also getting some values the lower layers get, you can eliminate a lot of color bleeding kinds of effects simply by having a clear picture of where the boundaries are.

In the end the result should be way closer to 19MP of color resolution than 5MP. I don't even think it's possible to have any image where you would only get 5MP of color resolution.

Yes, it is possible to construct an artificial image where the color resolution is 5 MP.

Here you have it:

Lets assume that you have an image that will expose the top layer equally for all 4 pixels. But, all four pixels have different colors. You cannot then detect those 4 colors. They will look the same.

Now, repeat this property over an area, and you will have 5 MP color resolution in that area, even though there are color changes for 20 MP.

NOTE: that the luminance also is down to 5 MP in this example.

So, it is a proof that (theoretically) you can have a resolution of 5 MP for both luminance and chrominance.